Yellow Yoshis are one of the color variants of the Yoshi species. In many games, a Yellow Yoshi serves as a palette swap option for Yoshi, having identical abilities with him. In several other cases, Yellow Yoshis have different abilities and stats than Yoshi, with their first appearance in Super Mario World, alongside other colored Yoshi variants, to have a special ability.

In Yellow Yoshi's first appearance in Super Mario World, its sprite features initially orange arms and brown shoes. Yoshi's Story depicts Yellow Yoshis wearing green shoes, and this has been the standard coloration for Yellow Yoshis since, with several exceptions. The current color scheme has a resemblance to modern Koopa Troopas, who are also depicted with yellow skin, similar facial features, and green shoes.

Screenshot of Yellow Yoshi using sand clouds to defeat a Rex, in Super Mario World.

In Super Mario World, Yellow Yoshis are one of the three colored variants that can be obtained in the game, the others being Red Yoshis and Blue Yoshis. All colored Yoshis can be found in the Star World as Baby Yoshis; Yellow Yoshis can be specifically found in Star World 3 and Star World 5. When they are first found, players have to feed them five enemies or objects before they mature into an adult Yoshi that they can ride on. Yellow Yoshis have the typical traits of a Green Yoshi, though Yellow Yoshis have the ability to create sand clouds when they land, which defeats most enemies nearby, and they fall faster when holding a Koopa Shell, in addition to spitting fireballs or flying if the shell is red or blue respectively.

Although fully grown Yellow Yoshis do not appear in New Super Mario Bros. U, as all Yoshis which can be ridden in the game are now green, Glowing Baby Yoshis are introduced instead. Glowing Baby Yoshis are infant Yellow Yoshis with the power to illuminate dark areas and briefly blind nearby enemies, similar to Bulb Yoshis. Like the other Baby Yoshis, they wear orange shoes instead of the green ones a Yellow Yoshi normally wears.

Yellow Yoshi was made available as a playable character in Super Mario Run following the release of the version 2.0.0 update on March 22, 2017. It can be unlocked after purchasing Yellow Yoshi's House from the Kingdom Builder shop, which becomes available only if the player has collected 300 Blue Toads, 300 Green Toads, and 200 Purple Toads. Alongside having all the abilities of Yoshi, Yellow Yoshi can recruit more Yellow Toads in Toad Rally.

In Super Mario World 2: Yoshi's Island, a Yellow Yoshi is playable for every world's mid-fortress. In this game, their sprite retains their coloration from Super Mario World, but are featured with yellow arms rather than orange arms. In the remake, Yoshi's Island: Super Mario Advance 3, Yellow Yoshi has green shoes to be consistent with its appearance from Yoshi's Story.

A baby Yellow Yoshi appears as a playable character in Yoshi's Story, alongside other colored Yoshis. The Yellow Yoshi generally likes yellow food, with its favorite fruit being bananas. Yellow Yoshi has also received a palette change, with it donning green shoes instead of brown shoes from the previous games. This appearance would be Yellow Yoshi's standard look in future installments.

In Mario & Luigi: Partners in Time, a Yellow Yoshi is among the initial group of Yoshis hiding from Yoob in Yoshi's Island. After the group is discovered by Mario, Luigi, Baby Mario, and Baby Luigi, all of the Yoshis run away and end up being eaten by Yoob. Later, after the heroes end up eaten by Yoob, they find the Yellow Yoshi, who is now lying on the floor with hunger. There is a nearby piece of fruit that can be given to the Yellow Yoshi, who immediately feels rejuvenated and runs to help the other Yoshis push a Chomp Rock down Yoob's stomach. Later, Yellow Yoshi helps the other Yoshis push the Chomp Rock out of the way of a doorway, and run into it once a path has been cleared. The Yoshis then take refuge in a side room, where the Yellow Yoshi only complains about wanting more food. Once Sunnycide is defeated, all of the Yoshis immediately escape Yoob. The Yellow Yoshi, along with the other Yoshis, briefly believe that Baby Bowser saved them until Toadbert explains the situation to them, who promptly thank the heroes.

A Yellow Yoshi appears in Mario & Luigi: Paper Jam in the Gloomy Woods village. He has found a huge melon the Mario Bros. want to feed a Wiggler blocking their path. When they ask for the melon, the Yoshi challenges the brothers to a race, with the winner getting the melon. During the race, the Yellow Yoshi flutter jumps to cross gaps, along with ground pounding when the Mario Bros. are nearby. When the Mario Bros. win the race, the Yoshi reluctantly gives up the melon.

Yellow Yoshi appears in Mario Tennis Open as a downloadable QR code character. Like Bowser, Donkey Kong, Wario, and Metal Mario, he is a power type character. Though not as powerful as the other characters in his type class, he offers more speed and agility than the other power characters, and he is the most powerful Yoshi variant. He is the slowest Yoshi variant with the least control however. Yellow Yoshi, alongside the other colored Yoshi variants, has sets of gear for Miis that players can purchase off the shop. If Yellow Yoshi's tennis racket is combined with the Yoshi costume, the Mii additionally receives a bonus.

A Yellow Yoshi is playable in Mario Kart: Super Circuit, exclusive to the multiplayer Game Boy Advance link play modes of the game, when players choose the Single Game Pak option. In this mode, players use Yoshi and his colored variants, where a Yellow Yoshi is played by player 4.

A Yellow Yoshi is one of the many character cameos and props used in Yoshi Park 1 from Mario Kart Arcade GP 2. During the first lap inside the first amusement park attraction, Yellow Yoshi is one of the Yoshis that pop out of eggs towards the players in the first lap of the course.

In Mario Kart 8, Yellow Yoshi appears as an alternate skin for Yoshi, unlocked by purchasing both the Legend of Zelda and Animal Crossing DLC packs. Yellow Yoshis can also be seen cheering at the sides of some of the courses, and certain ones may hum Totaka's Song. In Mario Kart 8 Deluxe, Yellow Yoshi is available from the start, and also appears as the 200cc staff ghost for 3DS DK Jungle.

Yellow Yoshi appears as an alternate color of Yoshi in Mario Hoops 3-on-3. The alternate colors are unlocked by achieving a silver trophy in the Flower Tourney in Hard Mode. The player must hold the or while putting normal Yoshi in the hoop during character selection.

In Mario Super Sluggers, a Yellow Yoshi is a team player. Among all of the playable Yoshis though, it had the weakest running abilities though he hits balls harder than the team player Yoshis aside from Red Yoshi, having a batting stat of 4/10. Yellow Yoshi runs slower than Red Yoshi, but has a stronger fielding stat than Red Yoshi. As with all the other Yoshis, Yellow Yoshi has Tongue Catch as its special ability, where it can retrieve balls from far away while fielding. Also as with all palette swap characters, it shares the same chemistry with the other Yoshis. In Challenge Mode, it is found in Yoshi Park by ground pounding next to a tree near the rainbow bridge leading to Birdo.

Yellow Yoshi also appears in Mario Sports Mix, as an alternative coloration of Yoshi. The Yellow Yoshi can be unlocked by playing 20 matches with Yoshi or completing the Yellow Yoshi mission at the Flower Cup alternate route.

A Yellow Yoshi appears in Paper Mario: Color Splash in The Emerald Circus, where it is found in a cage along with other wild Yoshis. Once the Yoshis break out of their cage, the Yellow Yoshi can attack Mario with its tongue, eating one of his Battle Cards if he doesn't block the attack.